The present invention relates to a movable ligating band dispenser, and in particular, to a movable ligating band dispenser that can assume a retracted position, to provide a substantially unimpaired field of view for an image sensing device of a hosting endoscope or laparoscope as well as greater mobility during exploration for such devices, and an extended position, for enabling a conventional ligation procedure.
Ligation is a medical procedure in which an elastic band, or ligating band, is placed about tissue to prevent fluid flow therethrough. Where a ligating band is placed about, for example, a ballooning varix, polyp, hemorrhoid, or pre-cancerous lesion, a contracted ligating band induces fusion and healing in the base tissue and subjects the ligated tissue to necrosis. The necrotic tissue eventually separates from the surrounding tissue and passes into the human system. Alternatively, ligation may also be used for purposes of sterilization, wherein a ligating band may be placed over a folded loop portion of a Fallopian tube or a vas deferens to prevent the passage of internal reproductive fluids.
Means for delivering ligating bands, or ligating band dispensers, take various forms. One such form is a dedicated ligating band dispenser instrument which has a dispensing portion at a distal end, an actuating mechanism at a proximal end, and a typically rigid shaft therebetween. These instruments are useful for ligating tissue in which the user has access to the tissue to be ligated, e.g., tissue exposed through an invasive surgical procedure.
In contrast, ligating band dispensers may be positioned on the distal tip of an endoscope or a laparoscope. An endoscope is a conventional medical device used for viewing, exploring, and delivering therapies to internal regions of a patient. A laparoscope is a specialized endoscope for viewing a patient""s peritoneal cavity. Unlike dedicated ligating band dispensing instruments, an endoscope allows minimally invasive intrusion into a patient.
FIGS. 1 and 2 illustrate a conventional endoscope. Endoscope 10 has a control portion 12 and a insertion portion 14 terminating at insertion tip 16. Insertion portion 14 is of such a length to permit access to internal regions of a patient.
FIG. 2 illustrates the face of insertion tip 16. A number of channels extend from the control portion 12 to the insertion tip 16, where the channels terminate in functional outlets 18-26. For the purposes of this example, outlet 18 is a light source; outlet 20 is a wide-field image sensing device, which transmits a video or fiber optic signal to a coupled monitor or eyepiece (not shown) at control portion 12; outlet 22 delivers a stream of water or air for clearing the image receiving device or flushing an internal bodily region; and outlet 24 is an outlet to a working (or biopsy) channel. Inlet 28 of the working channel can be coupled to a suction device or a lavage fluid source (not shown) or can receive various medical instrumentation (not shown) for passage through the working channel and outlet 24. Optional outlet 26, for larger diameter endoscopes, is an outlet for a second working channel. A second working channel allows additional operations in a manner consistent with the working channel described above.
Endoscope ligating band dispensers are fixedly mounted about and protrude from insertion tip 16 of a hosting endoscope, wherein such dispensers carry one or more expanded ligating bands about their outer diameter. Projecting from insertion tip 16, conventional dispensers inherently narrow the field of view of the image sensing device of outlet 20. In an effort to improve such impairment, some conventional devices are fabricated from a transparent material. While such material may facilitate the outward passage of light from outlet 18, such material does not practically improve the field of view for the wide-field image sensing device. Specifically, the use of transparent material commonly induces distortion about the periphery of a displayed image. Distortion is a product of both the curvature of the dispenser and the accumulation of bodily fluids about the outer surface of the dispenser. Ligating bands stored on the outer diameter of these dispensers further obstruct the field of view through the dispenser material.
A conventional endoscope ligating band dispenser is shown in FIG. 3. Dispenser 1000 is capable of dispensing multiple ligating bands 1002, whether individually or sequentially. Typical of the prior art, dispenser 1000 is cylindrical and hollow in nature, where an inner periphery of dispenser 1000 defines a cavity and an outer periphery carries the ligating bands 1002. Dispenser 1000 projects from the distal end of insertion tip 16. Accordingly, dispenser 1000 inhibits the field of view of a wide-field image sensing device (not shown) of the hosting endoscope in accordance with the limitations of conventional devices outlined above.
Conventional dispensers, such as dispenser 1000, increase the length of insertion tip 16. A ligating band dispenser-equipped endoscope is commonly used within a hollow body cavity, for example, an esophagus. Insertion tip 16 must assume almost a 90xc2x0 bend with respect to the longitudinal axis of the insertion portion 14 to obtain a clear view normal to the inner surface of an esophagus. The additional length of the ligating band dispenser from insertion tip 16 can significantly restrict the motion and flexibility of insertion tip 16 within a hollow body cavity. Accordingly, the added length, coupled with the severely restricted peripheral view, makes the presence of conventional ligating band dispensers an operational liability during the exploration and placement phases of ligation procedures.
The present invention is directed to a ligating band dispensing device adapted to be movably received on a distal end of an insertion portion of an endoscope having a fixed seal. The dispensing device has a proximal end that movably receives an insertion portion of an endoscope, a distal end, and an interior surface that, when in an operative position, at least partially encompasses a portion of the insertion portion of the endoscope and at least a portion of the seal. The seal is adapted to establish a sealing relationship between the endoscope and the dispensing device during a ligation procedure. Operatively, the dispensing device is capable of movement from a retracted position to at least a dispensing position.
A dispensing device in accordance with another aspect of the present invention includes a ligating band dispenser, an actuating mechanism, and a sealing member for placement on the insertion portion of an endoscope. The ligating band dispenser is adapted to be slidably mounted on the distal end of the insertion portion of the endoscope. The actuating mechanism is coupled to the ligating band dispenser and is adapted to selectively effect movement of the dispenser from a first position to at least a second position, relative to the sealing member fixed to the insertion portion of the endoscope. In the second position, the distal end of the dispenser is distally spaced from the distal end of the endoscope, creating a volume substantially defined by the dispenser sufficient to perform a ligation procedure. In the first position, the volume is reduced to expose, at least in part, a face of the distal end of the insertion portion of the endoscope.
A system for dispensing a ligating band to ligate tissue in accordance with another aspect of the present invention includes an endoscope, a member, and a dispensing device. The endoscope has an insertion portion for insertion into a patient. The member is positioned on the insertion portion of the endoscope. The member further includes a proximal end that includes an abutting surface to abut a distal face of the insertion portion of the endoscope. The dispensing device is movably positioned on the insertion portion of the endoscope and is capable of movement from a retracted position to at least a dispensing position. At least a portion of the member is interposed between the dispensing device and the endoscope.
In operation, the present invention facilitates increased flexibility of motion and a greater field of view for an image sensing device of the hosting endoscope during a ligation procedure. More specifically, steps for ligating tissue may include providing a dispenser on a distal end of an insertion portion of an endoscope, said ligating band dispenser being coupled to a control portion with at least one control filament for selectively moving the dispenser from a retracted position to at least a dispensing position relative to the distal end of the insertion portion. The ligating band dispenser supports one or more expanded ligating bands. The insertion portion, including the dispenser is inserted into a patient, wherein the dispenser is in a retracted position relative to the distal end of the insertion portion. The insertion portion is then navigated to a desired tissue site. Once a tissue site is identified, the at least one control filament is manipulated so as to extend the dispenser to at least a dispensing position. The extended dispenser creates a volume substantially defined by the dispenser sufficient to receive that tissue to be ligated. Application of a suction or use of a mechanical instrument causes such tissue to be drawn into the volume, whereafter a ligating band can then be dispensed.
An object of the present invention is to provide an endoscope ligating band dispensing device which enables an improved field of view for an image sensing device of a hosting endoscope.
Another object of the present invention is to provide an endoscope ligating band dispensing device which may assume a first position for an increased field of view for an image sensing device of a hosting endoscope and may assume a second position for dispensing a ligating band.
Another object of the present invention is to provide a controller and an actuating device for an endoscope ligating band dispensing device to enable the selective retraction/extension of a ligating band dispenser as well as remote, selective ligating band dispensing.
Other objects and advantages of the present invention will be apparent to those of ordinary skill in the art having reference to the following specification together with the drawings.